Outer Ring Seal for a Bearing and Method of Installing the Same
A bearing has an outer ring with an annular side face with an outer ring raceway on an inner peripheral surface of the outer ring and an interface formed on an outer peripheral surface at an axial end portion of the outer ring adjacent the annular side face. A compressible element is disposed at the interface. A seal carrier is deformingly connected to the outer ring with a portion of the seal carrier conforming to the interface with the compressible element disposed therebetween forming a seal between the outer ring and the portion of the seal carrier attached thereto.
Latest RELIANCE ELECTRIC TECHNOLOGIES, LLC Patents:
- Two-Piece Bearing Cage with Side Face Grease Carrying Cavities
- Flexible Coupling Assembly with Embedded Torque Transmitting Elements
- Method of Installing a Permanent Magnet Motor in a Cooling Tower and a Shroud Used in Connection Therewith
- Waveform Expansion Sleeve for a Bearing
- Extension Member for a Flinger of a Bearing
The disclosure relates to a roller bearing comprising an inner ring and an outer ring each having a race which together form a bearing space in which rolling elements are accommodated. The bearing space is sealed by means of a first seal fixed on the outer ring and a second seal fixed on the inner ring. Leakage from and contamination ingress into the bearing space between the outer ring and the first seal is prevented by a compressible element disposed between the first seal and the outer ring.
Turning now to the drawings, and referring first to
In the embodiment illustrated in
The various components and exemplary configuration of the seals shown in
Similarly, the second seal 28 is secured to an interface surface 36 of the inner ring 18. The extension 34, again generally annular in shape, is deformed or crimped to conform to the interface surface 36, which may be similarly grooved or otherwise contoured. As mentioned above, the interface surface may include dimples, ridges, and other such anti-rotation or rigidification features, used for securement of the inner ring seal 28 to the inner ring 18. However, in the drawings, an annular groove is employed on the inner ring 18.
While
As set forth above, the first and second seals of the bearing assembly are preferably installed by plastic deformation of a portion of the seal components. In other words, the seal components include a metallic member which is crimped directly to the interface surface of the receiving ring. Generally speaking, the seal carrier is formed from a low carbon steel material which exhibits sufficient malleability to allow it to be crimped or deformingly connected to the outer ring. Other materials, such as aluminum, bronze, plastics, may also be used to allow the seal carrier to be deformingly connected to the outer ring.
A method and apparatus for installing seals on a bearing, like the first and second seals discussed above, is disclosed in a co-pending, co-owned application, entitled, “Method and apparatus for installing bearing seals and bearing incorporating same,” (U.S. application Ser. No. 09/966,487), the disclosure of which is incorporated by reference herein.
The crimping collet 50 is a single piece, metallic collet designed to contract upon entry into the tapered ring and pot, and to be released or expand for removal of the outer ring from the tool as described below. Accordingly, the crimping collet 50 includes a series of crimping sections 52 designed to be forced radially inwardly by the tapered ring during the crimping operation. Each crimping section 52 is formed at the end an elastically deformable leg 54. Slots 56 are provided between the legs 54 to facilitate the radial contraction of the collet during use.
A seal support cup 58 is positioned within the collet 50 for receiving the outer ring seal carrier 22. The seal support cup 58 thus receives and centers the outer ring seal prior to the crimping operation. An upper cup 60 serves to exert force against the bearing outer ring when positioned in the installation system. For attachment of the outer ring seal to the outer ring, force is applied to the upper cup 60, as indicated by arrow 62 in
As shown in the drawings, the first seal extension 30, i.e., the portion of the seal carrier conforming to the anchor groove, the lip, and the side face of the outer ring, also forms a seal between the seal carrier and outer ring. The seal formed between the portion of the seal carrier conforming to the anchor groove, the lip, and the side face of the outer ring elements prevents the ingress of contaminants into the bearing space and the leakage of lubricant from the bearing space in the interface between the outer ring and the seal carrier. To enhance the seal formed between the seal carrier and the outer ring, a compressible element 80 is disposed between the interface 32 and the portion of the seal carrier deformingly connected to the outer ring. The compressible element may be placed in the outer ring interface, on the extension of the seal carrier to be deformingly connected to the outer ring interface, or on both surfaces prior to operations to deformingly connect the seal carrier to the outer ring. Preferably, the compressible element comprises a silicone material. Various rubber materials may also be used. The compressible element reduces the amount of clamping force needed to deformingly connect the seal carrier to the outer ring while still providing sufficient frictional force between the interface 32 and the seal carrier 26 such that the seal 22 will not spin when subjected to torque from the wiper element legs 29′, 29″ bearing on the spinning inner ring 18. By using the compressible element, the clamping force may be reduced, thereby minimizing potential deformation of the outer ring and outer ring raceway while still forming a sufficiently rigid connection and seal between the seal carrier and outer ring.
Generally speaking, high clamping forces are required to deformingly connect the seal carrier to the outer ring to form the seal and to ensure the seal carrier does not rotate relative to the outer ring during operation of the bearing. Sometimes, the high clamping forces permanently deform the outer ring, thus leading to increased bearing temperatures and a reduction in bearing life. The use of a compressible element 80 in the interface 32 reduces the clamping forces required to deformingly connect the seal carrier to the outer ring with a seal therebetween sufficient to prevent leakage from the bearing space and with sufficient frictional force to resist torque applied to the seal carrier through rotation of the shaft.
Additionally, the use of a compressible element 80 between the extension 30 and the interface 32 accommodates for any deformation or distortion of the interface, for instance, from heat treating of the outer ring. In one method of bearing manufacture as shown in the flow chart of
Accordingly, the methods disclosed herein may be used in connection with any thin walled seal with a seal carrier crimped thereto, thus allowing the seal carrier to be deformingly connected to the thin walled section using relatively lower clamping forces and, thus, contributing less to potential deformation of the thin walled section. This application is particularly suited for roller bearings units where the overall axial width of the outer ring is controlled. Providing the outer ring with an interface, such as an anchor groove, and deformingly connecting the seal carrier to the interface and extending the seal carrier along an axial side face of the outer ring allows the overall axial width of the outer ring to be less than alternative designs involving a seal carrier extending from the inner diameter surface of the outer ring. For instance, forming a groove in the inner diameter surface of the outer ring and extending the seal carrier from the groove toward the inner ring generally requires the outer ring to have an increased axial width to accommodate the groove and the lip. On the other hand, forming the interface on the outer peripheral surface of the outer ring and extending the seal carrier therefrom allows for an overall, more compact bearing design.
While specific embodiments have been described in detail in the foregoing detailed description and illustrated in the accompanying drawings, those with ordinary skill in the art will appreciate that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limited as to the scope of the invention which is to be given the full breadth of the appended claims and any and all equivalents thereof.
Claims
1. A bearing comprising:
- an outer ring having a generally annular side face with an outer ring raceway on an inner peripheral surface of the outer ring, and an interface formed on an outer peripheral surface at an axial end portion of the outer ring adjacent the annular side face;
- a compressible element disposed at the interface;
- an inner ring having an inner ring raceway formed on an outer peripheral surface thereof;
- a plurality of rotational elements rotatably positioned between the outer ring raceway and the inner ring raceway; and
- a seal carrier extending from the outer ring toward the inner ring, the seal carrier deformingly connected to the outer ring with a portion of the seal carrier conforming to the interface with the compressible element disposed therebetween forming a rigid connection and seal between the outer ring and the portion of the seal carrier attached thereto.
2. The bearing of claim 1 wherein the interface comprises a groove.
3. The bearing of claim 2 wherein the coterminous edge between the outer ring side face and the groove includes a lip and the portion of the seal carrier deformingly connected to the outer ring conforms to the lip.
4. The bearing of claim 1 wherein the compressible element comprises a silicone material.
5. The bearing of claim 1 wherein the seal carrier abuts the outer ring side face.
6. A method comprising:
- providing an outer ring having a generally annular side face with an outer ring raceway on an inner peripheral surface of the outer ring, and an interface formed on an outer peripheral surface at an axial end portion of the outer ring adjacent the annular side face;
- disposing a compressible element at the interface;
- providing an inner ring having an inner ring raceway formed on an outer peripheral surface thereof;
- disposing a plurality of rotational elements between the outer ring raceway and the inner ring raceway; and
- deformingly connecting a seal carrier to the outer ring in a manner such that a portion of the seal carrier conforms to the interface with the compressible element disposed therebetween to form a rigid connection and seal between the outer ring and the portion of the seal carrier attached thereto.
7. The bearing of claim 6 wherein the interface comprises a groove.
8. The method of claim 7, wherein the coterminous edge between the outer ring side face and the groove includes a lip; and the step of deformingly connecting the portion of the seal carrier to the outer ring includes conforming the seal carrier to the lip.
9. The method of claim 6, wherein the compressible element comprises a silicone material.
10. The method of claim 6, wherein the seal carrier abuts the outer ring side face.
11. The method of claim 6, further comprising heat treating the outer ring after forming the interface in the outer ring.
12. The method of claim 12, further comprising disposing the compressible element between the portion of the seal carrier deformingly connected to the outer ring and the interface in a manner to accommodate any distortion of the interface caused by heat treating the outer ring.
Type: Application
Filed: Jun 10, 2009
Publication Date: Dec 16, 2010
Applicant: RELIANCE ELECTRIC TECHNOLOGIES, LLC (Greenville, SC)
Inventor: William Gregory Hewitt (Taylors, SC)
Application Number: 12/482,018
International Classification: F16C 33/72 (20060101); B21D 53/10 (20060101);